let g:(a: number, b: number)=>number=function (a: number, b: number): number {
    return a + b;
}

let k: (n: number, m: number) => number = (n: number,m: number):number => {
    return n + m;
};
let i:number[]=[1,2,3]
interface Per{
    name:string,
    age:number
}
let a:Per={
    name:"zs",
    age:18
}
let pp:string|number|boolean=56
pp="sd"
pp=true
let arr5:(string|number)[]=[67,"aa"]
let ppp:55|"s"="s"
let pppp:55|string
type ooo=  string|number|boolean
let vv:ooo="ls"
interface wer{
    name:string,
    height:number
}
type qwe={
    name:string,
    height:number
}
// interface可以继承extends
interface SubPer extends Per{
    id:number
}
let lll:SubPer={
    name:"zs",
    age:18,
    id:1,
}
// 交叉
type pppp1=Per&{id:number}
let lll1:pppp1={
    name:"zs",
    age:18,
    id:1,
}
// 断言 as
let  e1:unknown = 56;
(e1 as number).toFixed(2)



